Identification of any publication in this section or any section of this application is not an admission that such publication is prior art to the present invention.
The compound 3-Amino-3-cyclobutylmethyl-2-hydroxypropionamide has the structure of Formula I:

The compound of Formula I is a key intermediate used in the preparation of the hepatitis C virus (“HCV”) protease inhibitor (1R,2S,5S)-3-azabicyclo[3,1,0]hexane-2-carboxamide, N-[3-amino-1-(cyclobutylmethyl)-2,3-dioxopropyl]-3-[(2S)-2-[[[1,1-dimethylethyl)amino]carbonylamino]-3,3-dimethyl-1-oxobutyl]-6,6-dimethyl having the following structure:
The compound of Formula Z is useful for treating hepatitis C and related disorders. Specifically, the compound of Formula Z is an inhibitor of the HCV NS3/NS4a serine protease.
Processes for preparing, the compound of Formula Z, using the compound of Formula I or salts thereof are described in each of U.S. Pat. No. 7,012,066 and U.S. Pat. No. 7,244,721, the entire contents of which are hereby incorporated fully herein by reference.
U.S. Pat. No. 6,992,220 (hereinafter “the '220 patent”) describes a process for preparing the compound of Formula I and salts thereof. The process of making the compound of Formula I and various salts thereof described in the '220 patent is presented in Scheme A, below.